This is an AU I made up a hour or two ago, and I'll be posting other AUs such as Underfell, Flowerfell, Underswap, Swapfell, and more that you want. Anyways, here's the story line:

Frisk is an angel, all the other monsters are demons, Chara's a fallen angel, and Asriel is an angel that's soul has been consumed by a demon. Frisk must fly down into the Underground-or hell-to save Asriel, however the more time she spends there the more his wings start digging into her blood. Angel wings are white, and neat, but fallen angel wings (in this AU at least) are blood red, and they look like they'll fall apart. Fallen Angel wings are red because the wings only fly when an angel is an angel, not a fallen one, the the wings drink the blood of the angel to support the wings. If a fallen angel flies to much, they'll pass out.

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Routes

Neutral Route- Frisk kills Asgore, but finds he doesn't have Asriel's soul. They've checked everywhere else, so she uses Asgore's soul to leave hell so she can fly back to heaven. Chara becomes the Queen of Demons, because Toriel-despite being a demon-doesn't have the heart for it.

Pacifist Route- The demon that consumed Asriel uses him as a puppet, and consumes the souls of all the other demons. Frisk must fight against this demon, but she doesn't do it alone, she calls upon the Seven Heavenly Virtues (the seven human souls) who had died in hell trying to save Asriel. Expect, the demon who had consumed everything was Gaster, who represents Sorrow, so Frisk needs one more Virtue. She calls upon Chara, the fallen angel, who represents Hope. All together, the Virtues create a power called Determination, and they kill Gaster and save the demons and Asriel. Soon the angels and demons call a truce and live happily together on Earth.

Genocide Route- Frisk falls under the influence of Gaster, and fills everyone in hell, then submits to him as a loyal servant, a surviving demon. Chara tries to stop Frisk, engaging in one last fight before Frisk kills her as well. Chara, in her dying moments, says that Frisk had no idea what she'd done, and later on after Earth has been destroyed by the two of them, Gaster reveals that there were two Charas. A good Chara, the representative of hope, and the evil Chara, the one with Gaster. This is because Chara spilt her soul in half to keep from going under the demonic influence. The demon Chara kills first for killing herself, then processed to kill Gaster, and then erase earth.

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Cannon Characters
«Frisk/Chastiy» Open
«Toriel/Gluttony (mostly used with food, but it also means to keep info to yourself (sorta) and she tried to keep Frisk a secret, sooo)» Open
«Sans/Sloth» Open
«Papyrus/Pride» Open
«Undyne/Wrath» Open
«Alphys/Envy» Open
«Mettaton/Lust» Open
«Chara/Hope» Taken by me
«Flowey» Open
«Asriel» Open
«Gaster/Sorrow»
«Yellow Soul/Justice/Humility» Open
«Green Soul/Kindness» Open
«Light Blue Soul/Patience» Open
«Orange Soul/Bravery/Diligence» Open
«Blue Soul/Integrity/Liberality» Open
«Purple Soul/Perseverance/Abstinence» Open

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Cannon Appearances

Frisk:
-Male
•Short brown hair, think Danisnotonfire hair, expect the fringe is in the front
•Gold eyes
•tan skin
•A white and gold sweater (white instead of blue, gold instead of purple)
•gray pants
•converse
•Neat, big, white angel wings
•when he opens is eyes, his halo appears on his head
-Female
•short brown hair, this style

•Gold eyes
•tan skin
•A white and gold sweater (white instead of blue, gold instead of purple)
•gray pants
•converse
•Neat, big, white angel wings
•when she opens her eyes, her halo appears on her head

Chara:
-Male
•Light brown hair, messy, this style
•Brown eyes with red tint
•Dark circles under eyes, because the pain from the wings doesn't let him sleep
•Always has a pained look in eyes (again, from wings)
•Gold heart locket
•black sweater with an empty, bleeding heart on it, long sleeve
•Old baggy pants, yet they fit well
•No shoes
•Big wings, but since he can't take care of his wings anymore due to being a fallen angel and the never ending pain, his big wings look small, and messed up
•Male version of this:

-Female
•Light brown hair, messy, twintail
•Brown eyes with red tint
•Dark circles under eyes, because the pain from the wings doesn't let him sleep
•Always has a pained look in eyes (again, from wings)
•Gold heart locket
•Black sweatshirt with empty bleeding heart on it, long sleeved
•brown ripped shorts
•No shoes
•Big wings, but since he can't take care of his wings anymore due to being a fallen angel and the never ending pain, his big wings look small, and messed up
•pretty much this: (yes I put the same picture twice

Asriel:
-Same goat boy, small horns
-Same sweater as Frisk
-Black pants
-No shoes

Sans:
-Pretty much same fat skeleton
-All black jacket
-blood stained gray shirt
-same shorts
-Black sippers

Papyrus:
-Pretty much Undertale Paps and Underfell paps fusion
-same style as UT Paps, but the colors of Underfell

Toriel:
-Blood stained purple ruin dressed

Asgore:
-Blood stained version of his old self
-Black eye sockets

Everyone else:
-pretty much a blood stained version of UT them, and with black sockets instead of eyes

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Please do alter your character for this AU along with many others